Hi Trinity, and Welcome to the club.
I have come across the fix and go kits, found that they really could only fix one tyre, so I have always ben keen on the spare wheel.
I have one on my s type which fits in neatly and anything that doesn't fit in the boot goes on to the back seat.
Personally, I would stick with the spare wheel, and bags can go in the space behind the from seats.
Regards
Peter,